To overcome the disadvantage that in a piece of furniture having a flap device supporting a top plate to be flapped to the furniture body to thereby enable efficient storage with the top plate locked in an erect position, only one end of the top plate is grounded so that pressure is applied to the flap device to break down in lodging the furniture.

This furniture includes a leg 3 as a furniture body provided with a pair of bases 31 laterally separated from each other and expansible at least in the longitudinal direction, and supports 32 erected from the bases 31, in which the bases 31 are extended forward over each support joint part 31y thereof joined to the supports 32, and a flap device 1 supported on the leg 3 to flap the top plate 2. The furniture is provided with a locking device 6 for locking the top plate 2 in the substantially horizontal working position, and also locking the top plate 2 in an erected storing position, whereby when the top plate 2 is laid down to be grounded, the state of locking the top plate 2 in the storing position is released so that the substantially whole surface of the top plate 2a can be grounded.